JP3702762B2 - Humidification method and humidifier - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a humidification method and a humidifier, and more particularly, to a two-fluid atomization type humidification method and humidifier used in a clean room facility of a semiconductor manufacturing factory, a paper diaper manufacturing factory, and the like.
[0002]
[Prior art]
As a humidifier used in a clean room facility of a semiconductor manufacturing factory or a manufacturing factory of a disposable diaper, there is a two-fluid atomizing humidifier. This humidifier simultaneously blows water and compressed air from the two-fluid nozzle to humidify the room. The water blown from the two-fluid nozzle is atomized by the shearing action of the compressed air blown at supersonic speed. Further, when the compressed air blown out from the two-fluid nozzle collides with each other, the shearing action by the compressed air works mutually and ultrasonic waves are generated, and the droplets in the humidified air are further atomized. Thereby, the homogenized humidified air is supplied indoors.
[0003]
However, previous humidifiers have a problem that the amount of static electricity in the room increases because the droplets in the compressed air are charged with random polarity when the compressed air collides with each other. When the amount of static electricity in the room increases, for example, a semiconductor is destroyed in a clean room of a semiconductor factory, or paper dust is charged in a paper diaper factory, causing a fire. Therefore, it is considered to suppress the charging phenomenon of water by bubbling carbon dioxide to increase the conductivity of atomized water.
[0004]
[Problems to be solved by the invention]
However, in the conventional humidifier, the amount of static electricity in the room may be high because the water to be atomized is not adjusted to the optimum conductivity.
[0005]
The present invention has been made in view of such circumstances, and an object thereof is to provide a humidification method and a humidifier that can humidify a room while keeping the amount of static electricity in the room low.
[0006]
[Means for solving the problems]
In order to achieve the above object, the invention according to claim 1 is a humidification method for supplying carbon dioxide to water, atomizing the water and supplying the water to the humidification target area, based on the humidity of the humidification target area. The supply amount of the carbon dioxide amount is adjusted.
[0007]
According to a second aspect of the present invention, in order to achieve the above object, a humidifier for atomizing water and supplying it to a humidification target region, supplying means for supplying carbon dioxide to the water, and supplying carbon dioxide by the supplying means A nozzle that simultaneously blows out the water and compressed air, an adjustment unit that adjusts the amount of carbon dioxide supplied by the supply unit, a humidity detection unit that detects the humidity of the humidification target region, and a detection value of the humidity detection unit And a control means for controlling the adjusting means based on the control means.
[0008]
According to the present invention, since an appropriate amount of carbon dioxide is supplied to water based on the humidity of the humidification target region and the water is atomized to perform humidification, humidification can be performed while keeping the static electricity amount of the humidification target region low.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Preferred embodiments of a humidification method and a humidifier according to the present invention will be described below with reference to the accompanying drawings.
[0010]
First, before explaining the humidifier according to the present invention, the theoretical basis for the construction of the humidifier according to the present invention will be described.
[0011]
The inventor of the present invention investigated the relationship between the electrical conductivity of water supplied to the nozzle and the potential change amount of the humidified air injected from the nozzle for each humidity.
[0012]
As shown in FIG. 1, the relationship between the electrical conductivity of water and the potential change amount of the humidified air has different characteristics for each humidity. Therefore, to control the potential change amount of the humidified air, it is necessary to adjust the conductivity of water according to the humidity. For example, when the amount of change in potential of humidified air is to be zero, the electrical conductivity of water may be set to a when the humidity is 50%, but the electrical conductivity is adjusted to b when the humidity is 40%, and the electrical conductivity is adjusted to c when the humidity is 30%. Must. That is, in order to control the potential change amount of the humidified air, it is necessary to obtain the humidity (or set the humidity) and adjust the conductivity of the water supplied to the nozzle according to this humidity.
[0013]
The present invention has been made based on the above-described knowledge, and the humidifier according to the first embodiment detects the humidity in the room and adjusts the conductivity of water according to the detected value. It reduces the amount of static electricity in the room while it is humidified. Further, the humidifier of the second embodiment sets the potential change amount and humidity of the humidified air, and adjusts the optimum electrical conductivity obtained from this set value while keeping the amount of static electricity in the room low. Humidification is performed.
[0014]
FIG. 2 is an overall structural view showing the humidifier 10 according to the first embodiment.
[0015]
As shown in FIG. 1, the humidifier 10 includes a spray device 12, an air source 14 that supplies compressed air to the spray device 12, and a pure water device 16 that supplies pure water to the spray device 12. . The compressed air sent from the air source 14 passes through the filter 18 and is removed, and then supplied to the spraying device 12 through the valve 20. The pure water produced by the pure water device 16 passes through the filter 22 to remove suspended matters, and then is sucked into the suction tank 28 via the valves 24 and 26 and supplied to the spraying device 12.
[0016]
The spraying device 12 is installed downward at a constant pitch from the side of the chamber 30 or from the ceiling surface. The spray device 12 includes a pair of nozzles 32 and 32, and jets compressed air (hereinafter, humidified air) obtained by atomizing pure water from the nozzles 32 and 32. As shown in FIG. 3, the pair of nozzles 32 and 32 are disposed to be inclined inward so that the blown humid air collides with each other. Each nozzle 32 is composed of a double pipe, and blows out pure water from the inner injection port 32A and also jets compressed air from the outer injection port 32B. The pure water injected from the injection port 32A is super atomized by the shearing stress of the compressed air injected from the injection port 32B at supersonic speed. Further, since the compressed air ejected from the nozzle 32 collides with each other, the shearing force by the compressed air acts on each other and ultrasonic waves are generated, so that the droplets in the compressed air are further atomized.
[0017]
As shown in FIG. 2, the humidifier 10 includes a carbon dioxide cylinder 34 and a mixing tank 36 as supply means for supplying carbon dioxide to pure water.
[0018]
The carbon dioxide gas sent from the cylinder 34 passes through the filter 38 and is removed, and then supplied to the tank 36 through the valve 40. The tank 36 is a device that mixes carbon dioxide gas and pure water, and the water sent from the pure water device 16 is diverted after passing through the filter 22 and supplied through the valve 42. The tank 36 is also communicated with the air source 14, and the compressed air that has passed through the filter 18 is supplied to the tank 36 through the valve 44. As a result, compressed air, pure water, and carbon dioxide gas are supplied to the tank 36, and the inside of the tank 36 is pressurized by the compressed air, so that the carbon dioxide gas is dissolved in the pure water. The water in which carbon dioxide is dissolved merges with pure water that does not pass through the tank 36, and then is supplied to the spraying device 12 through the valve 26 and the suction tank 28. Thereby, the water which absorbs a carbon dioxide and has electroconductivity is supplied to the spraying apparatus 12.
[0019]
The conductivity of the water supplied to the spray device 12 is detected by a conductivity meter 46. That is, the pure water that has passed through the suction tank 28 is divided and sent to the conductivity meter 46, and the conductivity meter 46 detects the conductivity of water. This detection signal is output to the control device 52 described later.
[0020]
Inside the chamber 30, an electrostatic quantity sensor 48 that detects the amount of static electricity and a hygrometer 50 that detects humidity are provided. The electrostatic quantity sensor 48 and the hygrometer 50 are electrically connected to the control device 52, and output each detection signal to the control device 52.
[0021]
The control device 52 adjusts the opening degree of the valves 20, 24, 26, 40, 42, 44 based on this detection signal. Thereby, while adjusting the quantity of the compressed air and pure water which are supplied to the spraying apparatus 12, the ratio of the carbon dioxide which melt | dissolves in a pure water changes, and the electrical conductivity of water is adjusted. Therefore, humidified air whose flow rate, humidity, and potential change amount are adjusted is blown out from the spraying device 12 into the chamber 30.
[0022]
Next, the operation of the humidifier 10 configured as described above will be described.
[0023]
When receiving the detection signals from the electrostatic quantity sensor 48 and the hygrometer 50, the control device 52 first obtains the optimal water conductivity for spraying from the nozzle 32. That is, the optimum potential change amount of the humidified air is obtained from the static electricity amount detected by the static electricity amount sensor 48, and the electric conductivity of water that becomes this potential change amount is obtained from the humidity detected by the hygrometer 50 using FIG. Ask. For example, when the humidity is 40% and the amount of static electricity is zero, it is desirable that the amount of change in potential of the humidified air supplied into the chamber 30 is zero. Therefore, the optimum water conductivity is b from the characteristic curve of FIG. It is obtained. In FIG. 1, the characteristic curve is shown at intervals of 10% humidity. However, if the characteristic curve is obtained at finer intervals, the optimum water conductivity can be obtained with high accuracy.
[0024]
Next, the control device 52 adjusts the opening degree of each valve 20, 24, 26, 40, 42, 44 so that the obtained electric conductivity b of water is obtained. For example, when the opening degree of the valve 40 is increased, the amount of carbon dioxide supplied to the tank 36 is increased, so that the conductivity of water can be increased. When water having the electrical conductivity b adjusted in this way is supplied to the nozzle 32, humidified air whose potential change amount is zero is blown out from the nozzle 32. Therefore, the inside of the chamber 30 can be humidified without increasing the amount of static electricity in the chamber 30.
[0025]
The above is a control method in the case where the amount of static electricity in the chamber 30 is zero, but when the inside of the chamber 30 is charged, droplets with reverse electrification are sprayed. For example, when the amount of static electricity in the chamber 30 is X (see FIG. 1), humidified air charged to −X is sprayed. In order to spray humidified air charged to -X, when the humidity is 40%, the conductivity of water needs to be d. Therefore, the control device 52 sets the conductivity of the water supplied to the nozzle 32 to d by adjusting the opening degree of each valve 20, 24, 26, 40, 42, 44. As a result, humidified air having a potential change amount of −X is blown into the chamber 30, the inside of the chamber 30 is neutralized, and the amount of static electricity in the chamber 30 is reduced.
[0026]
As described above, according to the humidifier 10 of the present embodiment, an appropriate electrical conductivity is obtained based on the humidity and static electricity in the chamber 30, and water adjusted to the electrical conductivity is supplied to the spraying device 12. Therefore, the inside of the chamber 30 can be humidified without increasing the amount of static electricity in the chamber 30.
[0027]
In addition, the humidifier 10 supplies pure water to the spraying device 12 and passes compressed air, pure water, and carbon dioxide gas through the filters 18, 22, and 38, so that impurities are blown out from the spraying device 12. There is no. Therefore, it is possible to prevent the display or display of the OA device from being contaminated by the humid air.
[0028]
The electrostatic quantity sensor 48 may not be provided, and in this case, control is performed so that the potential change amount of the humidified air is always zero.
[0029]
Below, the humidifier of 2nd Embodiment is demonstrated.
[0030]
FIG. 4 shows the relationship between the electrical conductivity of water and the set humidity in the chamber 30 for each potential change amount of the humidified air 30 based on the result of FIG.
[0031]
The humidifier (not shown) of the second embodiment is configured in the same manner as the humidifier 10 of the first embodiment shown in FIG. In addition, the set humidity in the chamber 30 and the allowable charge amount are input to the control device 52 in advance.
[0032]
When the set humidity and the allowable charge amount are input, the control device 52 uses the characteristic curve shown in FIG. 4 to obtain the optimum conductivity. For example, when the set humidity is input as 40 to 50% and the allowable charge amount is within -5 V, the control device 52 obtains appropriate water conductivities ef from the characteristic curve of FIG. And the electrical conductivity of the water sprayed from the nozzle 32 is adjusted similarly to 1st Embodiment. Thereby, humidified air having a humidity of 40 to 50% and within −5 V is blown out from the spraying device 12, so that the static electricity amount in the chamber 30 is maintained within an allowable range.
[0033]
As described above, according to the humidifier of the second embodiment, the inside of the chamber 30 can be humidified while maintaining the amount of static electricity in the chamber 30 within an allowable range. In the second embodiment, by setting the allowable range large, the supply amount of carbon dioxide supplied to the water can be reduced, and the running cost can be reduced.
[0034]
In the above-described embodiment, the number of static electricity sensors 48 is one, but a plurality of static electricity sensors 48, 48,... Further, the electrostatic quantity sensor 48 may be a potential sensor.
[0035]
【The invention's effect】
As described above, according to the humidification method and the humidifier according to the present invention, the supply amount of carbon dioxide is adjusted based on the humidity of the humidification target region, and the conductivity of water is adjusted. The humidification target area can be humidified while maintaining the amount.
[Brief description of the drawings]
FIG. 1 is a diagram showing the relationship between the electrical conductivity of water and the amount of change in potential of humidified air. FIG. 2 is an overall configuration diagram showing a humidifier according to the present invention. FIG. 3 is a cross-sectional view illustrating the nozzle shown in FIG. [Figure 4] Figure showing the relationship between room humidity and water conductivity [Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Humidifier, 12 ... Spraying device, 14 ... Air source, 16 ... Pure water device, 30 ... Chamber, 32 ... Nozzle, 34 ... (CO2) cylinder, 36 ... Tank, 46 ... Conductivity meter, 48 ... Electrostatic quantity sensor, 50 ... Hygrometer, 52 ... Control device

Claims (3)

A humidification method of supplying carbon dioxide to water, atomizing the water and supplying it to a humidification target area,
The humidification method characterized by adjusting the supply amount of the amount of carbon dioxide based on the humidity of the humidification object region. In a humidifier that atomizes water and supplies it to the area to be humidified,
Supply means for supplying carbon dioxide to the water;
A nozzle that simultaneously blows out water and compressed air supplied with carbon dioxide by the supply means;
Adjusting means for adjusting the amount of carbon dioxide supplied by the supplying means;
Humidity detecting means for detecting the humidity of the humidifying target area;
Control means for controlling the adjusting means based on the detected value of the humidity detecting means;
The humidifier characterized by providing. The humidifier according to claim 2, further comprising a detection unit that detects a static electricity amount or a potential of the humidification target region, and the adjustment unit is controlled so that a detection value of the detection unit falls within a predetermined range. .

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